Salal (Gaultheria shallon) is a plant species native to western North America. Salal is commonly associated with the Western poison oak. This plant’s leaves and berries are edible. The leaves and berries can function as an appetite suppressant and are often included in jams and pies.
I. Appearance and Characteristics
Gaultheria shallon is an evergreen shrub in the heather family (Ericaceae), native to western North America. In English, it is known as salal, shallon, or (mainly in Britain) gaultheria.
Gaultheria shallon is 0.4 to 3.05 meters (1+1⁄2 to 10 feet) tall, sprawling to erect. It is loosely to densely branched and often forms dense, nearly impenetrable thickets. The twigs are reddish-brown, with shedding bark. Twigs can live up to 16 years or more, but bear leaves only the first few years.
The leaves are alternate, evergreen, leathery, thick and egg shaped. They are shiny and dark green on the upper surface, and rough and lighter green on the lower. Each finely and sharply serrate leaf is 5 to 10 centimeters (2 to 4 inches) long. Each leaf generally lives for 2 to 4 years before it is replaced.
The inflorescence of flowers consists of a bracteate raceme, one-sided, with 5–15 flowers at the ends of branches. Each flower is composed of a deeply five-parted, glandular-haired calyx and an urn-shaped pink to white, glandular to hairy, five-lobed petals (corolla), 7 to 10 millimeters (1⁄4 to 3⁄8 in) long.
The fruit is reddish to blue, rough-surfaced, covered in tiny hairs, nearly spherical and 6 to 10 mm in diameter. The fruits are ‘pseudoberries’, or capsules made up of a fleshy outer calyx, and each fruit contains an average of 126 brown, reticulate seeds approximately 0.1 mm in length.
G. shallon grows in moist to dry, montane to lowland coastal conifer forests as well as forested peatland and swamps throughout the Pacific Northwest down to Southern California. It is a common coniferous forest understory species where shade is not heavy and may dominate large areas with its spreading rhizomes. Individual plants may live for hundreds of years, spreading from their rhizomes. The plant is sensitive to frost.
It is tolerant of salt spray and grows well on stabilized dunes, exposed slopes, and bluffs near the ocean, as well as in coastal brushfields and coastal shore pine and Sitka spruce forests. Salal tolerates moderate shade and does well in sun.
It grows in a variety of soils but prefers moist sandy or peaty soils, and commonly establishes on decaying wood and stumps or as an epiphyte in extremely humid areas.
Conifer regeneration is typically better on sites dominated by salal than on sites dominated by the western swordfern or vine maple, although it still competes with conifer seedlings for water, nutrients, and space. There are mixed reports on its impact on Douglas-fir regrowth; on some sites it may hinder it, but on others it may add nutrients to the soil and actually increase conifer regeneration.
II. How to Grow and Care
Sunlight and Soil
Salal is a part shade to full shade lover, this plant is best grown in moist or dry, acidic, well-drained soils.
Watering
Native to the damp, forested regions of North America, salal thrives in moist environments and is well-adapted to the understory’s humidity. This species exhibits a preference for consistent moisture but can tolerate short dry periods. Watering should be done once every 1-2 weeks, maintaining soil hydration without waterlogging. Typically grown as an understory plant in outdoor settings, salal benefits from mulching to retain soil moisture and mimic its natural leaf-litter environment.
Fertilizing
For optimal growth, salal thrives on balanced fertilizers (e.g., 10-10-10) in spring and high nitrogen blends during active growth. Fertilize salal biannually, sparingly to avoid root burn, which maintains foliage vigor and supports blooms. In fall, reduce fertilization to prevent new, frost-sensitive growth. Applying mulch can retain soil nutrients. Always water salal post-fertilization to aid absorption and minimize nutrient leaching.
Propagation
Salal is best propagated through cuttings during the warmer seasons, specifically spring and summer. It has a moderate propagation difficulty. Successful propagation is evident through root development, and ensuring moisture retention is crucial for optimal growth.
Transplanting
Transplant salal in the vibrancy of early-to-mid-spring, when growth is poised to surge. Choose shady, well-drained spots, akin to its natural woodland setting. If needed, amend soil with organic matter to mimic salal’s preferred environment. A friendly reminder to preserve root integrity during the process.
Repotting
Spring is ideal to repot salal, a lush bush that appreciates room for its wide spread. Every 2-3 years, upsize the container to encourage growth. Choose well-draining pots—a size larger than its current home promotes healthy roots. After repotting, maintain moist soil and partial shade to help salal acclimate and thrive in its new environment.
III. Uses and Benefits
- Ornamental uses
Salal is a great choice for shady or woodland gardens. It has decorative flowers and foliage that compliments cut flower arrangements. It works in borders and beds of conventional gardens and works well if planted with other plants that don’t need much direct sun, like rhododendron and ferns.
- Medicinal uses
The species has been used for its medicinal properties by local natives for generations, although its medicinal uses are not widely known. The leaves have an astringent effect, making it an effective anti-inflammatory and anti-cramping herb. Leaves prepared in a tea or tincture are thought to decrease internal inflammation (such as bladder inflammation), stomach or duodenal ulcers, heartburn, indigestion, sinus inflammation, diarrhea, moderate fever, inflamed/irritated throat, and menstrual cramps. A poultice of the leaf can be used externally to ease discomfort from insect bites and stings.
- Culinary uses
The dark blue berries and young leaves are edible and efficient appetite suppressants, both with a unique flavor. The berries were a significant food resource for some Native American tribes, who ate them fresh and dried them into cakes. They were also used as a sweetener, and the Haida used them to thicken salmon eggs. The leaves of the plant were also sometimes used to flavor fish soup.
More recently, the berries are used locally in jams, preserves, and pies. They are often combined with Oregon-grape because salal’s mild sweetness partially masks the former’s tartness.
- Use by animals
The leaves are browsed by deer and elk, and it is an important winter food for those species. Browsing is heaviest when other low-growing species become covered in snow; in Western Washington salal leaves composed 30.4% of deer diet by volume in January, compared to only 0.5% in June. The leaves have relatively low nutritional value, and deer which feed exclusively on them have shown signs of malnutrition, cementing their status as a winter and emergency food for ungulates. Beavers and the white-footed vole are known to feed on salal leaves, as are domestic goats and sheep in some areas.
The band-tailed pigeon, wrentit, various species of grouse, and numerous songbirds consume the fruit, as do mammals such as the red squirrel, black bear, black-tailed deer, Townsend’s chipmunk, and the Douglas squirrel.
Salal flowers are pollinated by hummingbirds, bees, and flies, and are browsed by deer.
It provides important cover and hiding places for a variety of species, from large ungulates to small birds and mammals.
